Field of the Invention
The present invention relates to a lens device to be mounted to an imaging apparatus for use.
Background
Hitherto, a monitoring camera lens device to be mounted to a monitoring camera for use is known (see, for example, Japanese Patent No. 5706049). This lens device includes a lens barrel, a ring member, and a mount member. An iris meter for controlling the aperture of the lens device is mounted to the lens barrel. One end of a cable (iris cable) is connected to the iris meter. The ring member is fixed to one end of the lens barrel in an optical axis direction of the lens barrel. The mount member is fixed to the ring member while sandwiching the ring member between the mount member and the lens barrel in the optical axis direction of the lens barrel.
In the lens device, an inner-wall ring and an outer-wall ring that have different diameters are formed in the ring member. A portion between the inner-wall ring and the outer-wall ring in the radial direction is a cable housing portion configured to house a part of the cable therein. Notches are formed at two locations in the outer-wall ring. Two protrusions for pressing the cable are formed on the mount member at positions corresponding to the notches of the outer-wall ring. The mount member is mounted so as to cover the cable housing portion. With the mount member mounted, the notches of the outer-wall ring and the protrusions of the mount member form an opening through which the cable is led toward the cable housing portion and an opening through which the cable is led out from the cable housing portion.
In the lens device, when the cable led into the cable housing portion between the inner-wall ring and the outer-wall ring through one opening is wound around the cable housing portion and is then led out through the other opening, a lead-out length of the cable led out from the lens device is reduced. In the lens device, when the cable led into the cable housing portion through one opening is led out through the other opening without being wound around the cable housing portion, the lead-out length of the cable led out from the lens device is increased. In this manner, the lens device described in Japanese Patent No. 5706049 can adjust the lead-out length of the cable led out from the lens device.
The lens device described in Japanese Patent No. 5706049 can adjust the lead-out length of the cable led out from the lens device as described above. In the lens device, however, the cable housing portion is covered with the mount member, and hence the lead-out length of the cable led out from the lens device cannot be adjusted unless the mount member is removed. Therefore, in the lens device, the work of changing the lead-out length of the cable led out from the lens device is complicated after the lens device is assembled.